Apparatus for handling sheet material

ABSTRACT

This application discloses transferring glass sheets from a horizontal conveyor to a vertical storage buck by permitting each sheet to ride over and drop off a driven roll at the discharge end of the conveyor and onto the angled face of a vacuum platen which receives, aligns and retains it. The sheet is then carried forward by the platen, swung from the receiving to a stacking angle and released, whereupon the conveyor and platen index themselves rearwardly and the platen returns to receiving position.

United States Patent Miller et Nov. 27, 1973 54] APPARATUS FOR HANDLINGSHEET 3,279,664 10/1966 Lynch 214/7 x 3,326,547 6/1967 Walters 61 al.214/1 BV MATERIAL Inventors: Alfred H. Miller, Toledo, Ohio;

George A. Dean, Kansas City, Mo.

Assignee: Libbey-Owens-Ford Company,

Toledo, Ohio Filed: May 30, 1972 Appl. No.2 257,973

Related U.S. Application Data Divisionof Ser. No. 56,529, July 20, 1970,Pat. No. 3,679,076.

U.S. Cl. .L 214/7, 271/87 Int. Cl. B65g 57/28 Field of Search 214/7, 6FS, 1 EV,

214/1 BD, 1 Q, l S; 271/69, 87

References Cited UNITED STATES PATENTS Guillaume 214/7 PrimaryExaminer-Robert J. Spar Attorney-Elmer L. Collins et al.

[57] ABSTRACT This application discloses transferring glass sheets froma horizontal conveyor to a vertical storage buck by permitting eachsheet to ride over and drop off a driven roll at the discharge end ofthe conveyor and onto the angled face of a vacuum platen which receives,aligns and retains it. The sheet is then carried forward by the platen,swung from the receiving to a stacking angle and released, whereupon theconveyor and platen index themselves rearwardly and the platen returnsto receiving position.

9 Claims, 21 Drawing Figures PATENTED NOV 2 7 I975 saw on orPATENTEBnuvm 1975 3,774,783

SHEET 08UF H PAIENTEU nuv 2 7 1915 SHEEF 08 0F APPARATUS FOR HANDLINGSHEET MATERIAL This is a division of application Ser. No. 56,529, filedJuly 20, 1970, and now US. Pat. No. 3,679,076.

BACKGROUND OF THE INVENTION 1. Field of the Invention The inventionrelates generally to the handling of sheet materials and moreparticularly to an improved method and apparatus for transferring sheetsfrom a given plane in one location to another plane in a differentlocation. I

While not limited thereto, the invention has proved particularlyvaluable in handling frangible materials such as glass and will bespecifically described in that connection here.

2. Description of the Prior Art In fabricating articles from sheet orplate glass on a high-volume production basis such as that encounteredin producing glazing closures for automobiles, it is often necessary toremove sheets from a conveyor for example, where they are supportedhorizontally, and to stack them on edge and substantially vertically ina storage area.

I-Ieretofore this type of transfer has been carried out either by hand,which is clostly and hazardous, or by employing suction lifting frames,which are best suited tolarge plate handling and are inherently slow andcumbersome.

SUMMARY OF THE INVENTION The present invention, on the other hand,provides a method and apparatus whereby sheet material in a wide varietyof sizes and shapes can be rapidly and accurately handled. For exampleit has been successfully used in handling, and stacking automobilewindshield blanks being discharged from the end of a conveyorat the rateof one every 2 seconds.

Generally speaking the method of the inventiorr'involves automaticallyreceiving a sheet from a source of supply, aligning it, carrying thealigned sheet forwardly toward and swinging it into discharge position,and

then releasing it; while the apparatus includes a vacuum platen forreceiving and manipulating the sheet, together with means for locatingthe sheet on the platen and for indexing the platen to successivelyadjacent sheet releasing positions.

An important object of the invention is to provide a method andapparatus of the above character that will permit glass sheets to behandled without injury thereto and that will insure the handled glassbeing stacked in a manner to minimize breakage thereafter.

Another object is the provision, in connection with such an apparatus,of a horizontal conveyor and a driven drop-off roll at the discharge endof the con veyor for controlling the speed at and the position in whichsheets are supplied to the receiving platen.

Another object is to provide a transfer apparatus that includesreceiving, conveying, stacking and indexing means embodied in a singleunitary structure and that can be incorporated in or used in conjunctionwith conventional processing, conveying, storing and/or handlingsystems.

Another object is the provision in such an apparatus of means forautomatically indexing'the same backwardly as it stacks successivesheets in face to face relationship and for maintaining such sheetstightly stacked together.

Further objects and advantages will become apparent during the course ofthe following description when taken in connection with the accompanyingdrawings.

In the drawings, wherein like numerals refer to like parts throughout:

FIG. I is a side elevation of a transfer apparatus constructed inaccordance with the invention and shown as positioned between aconventional feed conveyor and a storage buck with its platen inposition to stack the first sheet on the buck;

FIG. 2 is a similar view of the transfer apparatus but showing itindexed to its completely retracted position and with its platen insheet receiving position;

FIG. 3 is a plan view of the structure shown in FIG. 1;

FIG. 4 is an end view of the transfer apparatus looking from the feedconveyor toward the storage buck;

FIG. 5 is an end view on an enlarged scale of the transfer apparatus,looking from the buck toward the feed conveyor and with portions brokenaway;

FIG. 6 is a transverse sectional view on an enlarged scale takensubstantially along the line 66 in FIG. 3;

FIG. 7 is a side elevation of the input end of the transfer apparatussimilar to that shown in FIG. 1 but on an enlarged scale and with partsbroken away;

FIG. 8 is a similar view of the stacking end of the apparatus and withthe platen in receiving position;

FIG. 9 is a transverse sectional view taken substantially along the line9-9 in FIG. 3;

FIG. 10 is a fragmentary sectional view taken substantially along theline 10-10 in FIG. 3;

FIG. 11 is a, fragmentary sectional view taken substantially along theline 11-11 in FIG. 8;

FIG. 12 is an enlarged fragmentary sectional view of the sheet edgesupporting means on the platen and taken substantially along the line1212 in FIG. 5;

FIG. 13 is an enlarged, fragmentary, longitudinal, sectional view takensubstantially along the line 13l3 in FIG. 3;

FIG. 14 is a transverse sectional view taken along the line l4l4 in FIG.13;

FIGS. 15 through 18 are side elevations similar to FIG. 8 butillustrating various stages of acomplete operational cycle for thetransfer apparatus;

FIG. 19 is a schematic'diagrarn of one type of vac uum actuating systemfor the platen;

FIG. 20 is a schematic diagram of one type of air actuating system thatmay be provided; and

FIG. 21 is a schematic wiring diagram for the control system.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularlyto the drawings, a preferred embodiment of the invention is illustratedtherein as a transfer apparatus interposed in and forming part of acomplete processing, conveying, handling and storing system.

Thus, as shown in FIG. 11, the transfer apparatus comprises generally aconveyor section A which is adapted to receive and support successivesheets in the horizontal plane while advancing them along a definitepath, and a handling section B for receiving individual sheets from thesection A and transporting them to and stacking them substantiallyvertically in another area.

More specifically, the conveyor section A has an entrance or input end2Ito,which glass sheets 22 can be supplied, as from a feed conveyor 23,and a discharge end 24 from which the sheets are dropped onto a platen25 of the handling section B (see FIG. 15).

The handling section B comprises the receiving platen, 25, alreadyreferred to, an actuator 26 which is adapted to translate the receivingplaten horizontally toward and away from a storage buck 27, and anotheractuator 28 which rotates the receiving platen about a pivot point 29.

The receiving platen 25 is made up of a supporting frame-work 30,carrying a flat, rigid plate 31, which can be wood or metal having afacing 32 (FIG. 12) of a relatively soft, non-abrasive material, such asfelt, to provide a glass supporting surface 33.

As best shown in FIG. 5, the facing 32 has a cut-out portion 34 whichforms a cavity 35 in the glass supporting surface. A hole 36 formed inthe plate 31 communicates with the cavity 35 and a fitting is attachedto the back of the plate 31 over the hole 36 to connect the cavity to avacuum source (not shown) via a flexible hose 37. The cavity 35 is soshaped and located that it will be covered by a sheet 22 sliding downthe surface 33 and, when this happens a vacuum will be created in thecavity which results in a pressure differential across the sheet due tothe atmospheric pressure acting on its outer surface. The size of thecavity and the capacity of the vacuum source are such as to produce aforce capable of stopping a sheet as it slides down the surface 33 andof retaining it on the surface. Also the cavity is designed anddistributed across the facing in a manner not to cause undue pressureconcentration in any area of the glass and to tend to maintain thesheets relatively straight on the surface of the platen.

The frame 30 is made up of a plurality of box-section rails with each ofthe end rails 38 (FIG. having an extended portion to which are welded orotherwise attached pairs of plates to form yokes 39 which are drilledand reamed to serve as bearings about which the frame can pivot orswing. Thus, the frame 30 is carried by L-shaped arms 40 (FIGS. 1, 2, 8and 12) which are extensions of rods 41 received in linear bearingblocks 42 attached to a movable main frame 43. The arm and rodarrangement is the same on both sides of the frame and each arm 40 endsin an eye and is connected to the yoke 39 by means of a pin at the pivotpoint 29.

The bearing blocks 42 support the rods 41 for backand-forth movementprovided by the actuator 26, which comprises a pressure cylinder 44 alsomounted on the frame 43 and having its ram 45 connected to the rod 41 bya link bar 46. Only one cylinder is employed so, to transfer the motionto the other side of the platen 25, a crank arm 47 is provided that hasone end pivotally connected to the ram 45, along with the link bar 46,and the other end fixed to a pivot bar 48 that extends across theconveyor section (see FIG. 3) and is journaled in bearings 49 mounted ona portion of the frame 43. On the other side of the conveyor a similarcrank arm and link transfer the motion of the ram 45 to the rod 41 sothat the receiving platen 25 will maintain its alignment with theconveyor as it moves toward and away from it.

The amount of linear movement of which the receiving platen is capableis determined by the stroke of the ram 45 and can be adjusted by meansof a screw 50 (FIG. 7) at the rear of the cylinder 44. Furtheradjustment is provided by mounting the cylinder 44 to the frame 43 by abolt and slot arrangement designated by numeral 51 and which includes aplurality of mounting holes 52 in a mounting plate 53 secured to theframe 43.

The pivoting motion of the receiving platen 25 is provided by anotherpressure cylinder 54 (FIG. 8) which is mounted on the rods 41 to movetherewith and with the linear movement of the receiving plate 25 so thatthe pivoting action of the platen will be independent of its linearmovement or location. The mounting arrangement for the cylinder 54(FIGS. 3, 8) comprises a tie bar 55 on which the trunnion bracket 56 ofthe cylinder rests, and clamping blocks 57 and 58 which are fastened toeither end of the tie bar 55 and clamped around the rods 41 by means ofbolts 59. The trunnion bracket 56 is centrally mounted on the tie bar(FIG. 3) by means of a bolt and slot arrangement and foreandaftadjustment is made by selectively loosening or tightening four screws 60which are received in threaded plates 61 that are fixed to the tie barand bear against the edges of the bracket 56. The cylinder 54 pivots onits trunnion mount and its ram 62 is pivotally connected at 63 to theframe 30 of the receiving platen 25. The stroke of the ram can beadjusted by means of a screw 64 at'the rear of the cylinder.

This mounting arrangement allows the platen to be moved from itsreceiving position (FIG. 15), in which its upper end is adjacent theexit end 24 of the conveyor and its lower end is spaced away to locatethe platen at approximately a 30 angle to the vertical, to its stackingposition (FIG. 17) in which the entire platen has been translated awayfrom the conveyor and its upper portion has been rotated to the right tocross the vertical and locate the platen in position to deposit a sheeton the buck 27.

Although the vacuum means within the receiving platen is capable ofstopping a sheet as it falls off the end of the conveyor (FIG. 15) andof effectively retaining it against the platen during manipulation, itis generally preferred to provide mechanical means for supporting thesheet from an edge as well. Such means may be in the form of catches,designated by the numeral 65 (FIGS. 5 and 8) which will also act toinsure that the sheets will be properly aligned on the receiving platen25 in case the vacuum system fails to stop the sheets in perfectalignment every time;

Two of the catches 65 are sufficient when spaced apart along the bottomedge of the receiving platen 25 and located inwardly a short distancefrom the yokes 39 (See FIG. 5). The two catches are identical and,referring to FIGS. 5 and 12, each is pivotally attached as at 66 to ayoke portion 67 of a bracket 68, which is bolted to the underside of thelower rail 69 of the re ceiving platen frame 30 and has a sheetreceiving portion 70 which protrudes outward beyond the facing 32 on theplate 31. The portion 70 is provided with a pad 71, of a resilient,non-abrasive material which in the illustrative embodiment is made up ofa piece of 32- durometer polyurethane bonded to a steel backing andbolted to the catch.

To maintain each of the catches 65 in its normally protruding or raisedand receiving position, a spring 72 is operatively associated therewithin a manner tending to rotate it counterclockwise about the pivot point66 toward the position shown in FIG. 12. To this end, the catch 65carries an extended portion 73 in the form of a clevis whichextendsupward within the yoke portion 67 of the bracket 68. A rod 74 isreceived within the clevis and extends through a hole provided in a flatplate 75 which spans and is fastened to the yoke'67. The spring 72surrounds the rod and is larger than the hole so that it bears againstthe plate 75 and is compressed by a nut 76 and washer 77 at the end ofthe rod 74. Compression of the spring 72 against the plate 75 tends topull the rod 74 to the left or counterclockwise as viewed in FIG. 12,thus maintaining the catch 65 in its raised position. A screw 78threaded through the plate 75 bears against the extended portion 73 ofthe catch and can be used to limit the amount of counterclockwisemovement and so adjust the receiving position of the catch. 7

To move each catch 65 from its raised, receiving position as shown inFIGS. and 16 to its lowered, sheet edge releasing position as shown inFIG. 17, advantage is taken of the translation of the receiving platen25. Referring again to FIG. 12, a threaded rod 79 is pivotally attachedto the catch 65 below the pivot point 66 by means of a clevis 80. Therod extends back toward the frame 43 through a bracket 81 attached tothe frame. A tube 82 fits over the rod and is retained thereon bylocknuts 83 bearing on a collar 84 on the side behind the bracket 81 andon a washer 85 on the opposite side. A bearing block 86 attached to thebracket 81 receives the tube and supports the assembly forback-and-forth movement.

When the receiving platen is moved to the right (FIGS. 16 and 17 by thecylinder 44 acting on the arms 40 the rod 79 (see FIG. 12 also) moveswith the platen, sliding through the bearing 86 which is carried by thebracket 81 on the frame 43 and so remains stationary. As the platen 25approaches the limit of its forward' travel the collar 84 contacts theback of the bracket 81, stopping the rod 79, and continued movement ofthe platen 25 causes the catch 65 to rotate clockwise against the forceof the spring 72 to the lowered position shown in FIG. 17, allowing asheet supported on the platen 25 to slide off. When the platen 25returns toward its receiving position the spring 72 will cause the catchto move back to its raised position (FIG. 18).

To provide an additional holding force to the catch 65 when thereceiving platen 25 is in its receiving position (FIG; 15), a secondcompression spring 87 sur-' rounds the tube 82 and is interposed betweenthe bearing block 86 and the washer 85 at the end of the tube. Thisassists the spring 72 in maintaining the catch raised when a sheet dropsonto it, after sliding over the platen. ,Of course when the platensubsequently reaches the depositing or stacking position shown in FIG.17 this additional force is not required and at that time the spring 87will be relaxed by reason of the tube 82 having moved forwardly throughthe bearing 86.

Referring to FIGS. 15 through 1 8, which depict a typical operationalcycle, a sheet 22, moving along the conveyor section A in the directionof the arrow in FIG. 15, reaches the discharge end 24 and falls onto theplaten 25. through a series of positions shown in broken lines anddesignated by the letters a, b, c and d. In position d the sheet 22covers the cavity in the glasssupporting surface 33 of the platen and avacuum will be created in the cavity behind the sheet stopping andholding the sheet against the platen.

Then, by means responsive to decreasing pressure within the cavity, orby other convenient means, the vacuum is interrupted, allowing the sheetto slide down the surface 33 and onto the catches 65 as shown at e inFIG. 16. Once the sheet arrives at position e it is supportedand alignedon the catches 65 and the vacuum is restored to again draw the sheetagainst the platen and retain it in its aligned position.

Next fluid pressure is applied behind the ram 45 of the cylinder 44 totranslate the platen 25 to the right as shown in FIG. 17, and at thesame time pressure is applied behind ram 62 of pressure cylinder 54 torotate or tilt the platen about the pivot point 29. As the platenapproaches its fully extended position and its stacking angle (FIG. 17)the collars 84 on the catch release rods 79 contact the brackets 81causing the catches 65 to stop so that continued forward motion of theplaten 25 causes the catches to rotate to an out-of-the-way positionbehind the surface 33 of the platen. At the same time the vacuum isreleased to allow the sheet 22 to drop off the platen and into stackedposition on the buck 27. Once the sheet is dropped, pressure is appliedto the opposite ends of cylinders 44 and 54 and the platen is returnedto its receiving position as shown in FIG. 18, to receive another sheet.

In the cycle illustrated in FIGS. 15 through 18, the deposited sheet isshown as being added to an already existing stack of sheets 88 on thebuck 27. However, regardless of whether this is the case or'a freshstack is being started as shown in FIG. I, to successively stack aplurality of sheets in the manner described, provision must be made toindex or retract the position to be attained by platen 25, in depositingthe next sheet, each time a sheet is deposited so as to compensate forthe growth of the stack on which the platen is working.

According to the invention, this may be accomplished, first, byproviding means for varying the length of the conveyor section A,between a fully extended condition as shown in FIG. I and a fullyretracted condition as shown in FIG. 2; and, second, by shortening theconveyor a distance equal to the thickness of one glass sheet every timea sheet is deposited or stacked on the buck 27.

To this end, and referring particularly to FIGS. 1, 2, 3, and 9, theconveyor section illustrated is of the type employing a pluralityofnarrow belts 89 entrained over pulleys and driving pulleys 90 andpulleys 91 and 92 which are associated with the input end 21 of theconveyor are mounted to a stationary main frame 93 rigidly attached tothe floor as at 94. Pulleys 95, associated with the discharge end 24 ofthe conveyor are mounted on the frame 43 which, as previously described,carries the receivingplaten 25 and is movable relative to the stationaryframe 93 on rollers 96 mounted on the opposed side rails 97 thereof(FIG. 3). As illustrated in FIG. 10, the rollers 96 are V-shaped incross-section and horizontal side rails 98 of the frame 43 are providedwith V-shaped runners 99 which ride in the rollers 96.

Movement of the frame 43 is provided by a pressure cylinder I00 (FIGS.3, 7, 8) mounted on the stationary frame 93 and having its ram 101connected to the movable frame 43. The cylinder is designed to move theframe 43 to any extent required between its fully retracted position(FIG. 2) to its fully extended position (FIG. 1).

However, during normal operation sufficient pressure is constantlyapplied behind the ram 101 to bias the frame 43 toward the buck 27 inthe stacking area and this biasing pressure is provided by an air tank102 carried by the frame 93. To limit the movement of the frame 43 underthe biasing pressure, stop rods 103 are provided (FIG. 8) which arefixed to the frame 43 and located to contact the vertical backingsurface 104 of the buck 27 or the last sheet in the stack 88, dependingon whether a new stack is being formed or whether one or more sheetshave already been stacked.

The lengths of the rods 103 is adjusted, relative to the receivingplaten 25, so that when the receiving platen is at full extension, (FIG.17), the sheet-supporting surface 33 of the platen will be slightlybeyond the ends of the rods 103.

With this arrangement, each time the receiving platen 25 attains itsfull extension under pressure from the cylinder 44, to deposit a sheeton the buck 27, the sheet will have contacted and pressed against thebacking surface 104 of the buck (or another previously stacked sheet) toforce the frame 43 rearwardly on the rollers 96 and against the biasingpressure from cylinder 100. This movement of the frame 43 indexes theentire handling section B by carrying the rods 103 rearwardly to makeroom for the sheet being carried by the platen so that, when the vacuumin the platen is released, this sheet will drop downwardly into stackingposition with its lower edge resting on the horizontal supportingportion of the buck.

Then, when the receiving platen 25 is subsequently moved back to itsreceiving position by the retracting action of cylinder 44, the biasingcylinder 100 will force the stop rods 103 back up against the sheet thatwas just deposited on the buck, thus holding the section B in itsindexed position and insuring that this latest sheet is stacked tightlyagainst any previously deposited sheets.

Two of the stop rods 103 are adequate when spaced apart along the bottomedge of the receiving platen 25 and adjacent the mechanical catches 65(FIG. As best seen in FIG. 8, each stop rod comprises a 1-inch diameterrod having a threaded mounting portion 105 and a stop portion 106 whichis offset downward so that it just clears the horizontal support surfaceof the buck 27. The threaded portion of the rod is received in a bracket107 which is attached to the forward end of the frame 43 and retainedtherein by means of locknuts 108 which are threaded onto the rod andbear against the opposite ends of the bracket. To prevent the rod fromrotating out of position, a slot 109 may be formed in the rod to receivea set screw 110 threaded into the side of the bracket 107, and theposition of the end of the rod, relative to the fully extended locationof the platen 25 is set by adjusting the position of the locknuts 108 onthe rod. The ends of the rods 103 which contact the glass sheets on thebuck are provided with pads 1 l 1 of a resilient, non-abrasive material,for example a 39-35 durometer urethane, which is screwed or otherwiseattached thereto.

Obviously, when the frame 43 is moved relative to the stationary frame93 as described above, some provision must be made to maintain theconveyor belts 89 taut. As here shown this is accomplished by means oftake-up pulleys 112 and 113 (FIGS. 1, 2 and 7) which are mounted on abracket 114 carried at the rear end of the frame 43. By comparing FIGS.1 and 2 it will be seen that, as the distance between the input endpulley 92 and discharge end pulley 95 decreases, due to rearwardmovement of the frame 43, the distance between the take up pulleys 112-113 and the drive pulley 90 increases proportionately. Consequently therelative locations of the various pulleys provide a take-up loop in thebelts 89 which insures their remaining taut at all times. To initiallytension the belts the take-up pulleys 112 and 113 are mounted forrotation (FIG. 7) on a sliding bracket 115 which is retained in a slotformed in a bracket 114 carried at the end of frame 43. Tightening ofthe belt is achieved by means of a screw 116 which is threaded through aplate 117, attached to the bracket 114, and which bears against thesliding bracket 115. A jam nut 118 is provided on the screw 116 tomaintain its position.

The drive pulleys 90 areall mounted on a through shaft 119 (FIG. 6) bymeans of flanges 120 and an input pulley 121 is mounted on one end ofthe shaft to connect the conveyor to a rotary power source 122 (FIG. 3).The shaft 119 is suitably journaled in bearings 123 mounted on thestationary frame 93.

To properly support the belts on their relatively long sheet supportingrun between the input and discharge end pulleys 92 and 95, each belt 89has a support runner 124 (FIGS. 7, 8 and 14) which is suitably mountedon the frame 43 by means of brackets 125 and, as shown in FIG. 14, eachrunner is grooved to conform to the shape of the belt.

To insure that the sheets 22 will drop off the conveyor onto and inproper alignment with the receiving platen 25, drop-off rolls 126 (FIGS.6, 13 and 15) are provided between the belts 89 at the discharge end ofconveyor section A, and are mounted for both vertical and horizontaladjustment relative to the discharge end of the conveyor by suitablebolt and slot arrangements in support plates 127.

By positioning of the rolls 126, it is possible to control the angle atwhich the sheets 22 tilt and drop off of the conveyor or section A andfall onto the receiving platen 25 (See FIG. 15). Similarly, although therolls 126 can be mounted for free rotation and depend on the conveyorbelts 90 to drive the sheets onto and over them, they can, andpreferably are, driven at a controlled speed slightly faster than theconveyor which results in their being positively drawn off the conveyorto better control the manner in, as well as the speed at,

which the sheets drop down onto the platen 25.

As shown in FIG. 13, the drive system comprises a gear motor'130, atransfer shaft 131 (FllG. 6) which links the two pairs of drop off rolls126 on opposite sides of the conveyor, and associated sprockets andchains to transmit the power from the gear motor 130 to the transfershaft 131 and then to the pairs of rolls 126. It has been found thatsheets of various sizes and shapes require different drop-off rollspeeds for optimum performance, and that speeds below as well as abovethe conveyor speed may be desirable. The output speed of the gear motor130 can be varied to meet all of these requirements.

AIR AND VACUUM SYSTEMS Following through a typical operational cycle, asa sheet 22 (FIG. 15) reaches the exit end 24 of the conveyor section itrides up onto the drop-off rolls 126 and over the edge of the conveyoruntil it drops and slides down onto the receiving platen 25. Referringto the vacuum diagram (FIG. 13), vacuum pump 135 is normally energizedand vacuum solenoid valve SV1 controlling the vacuum on the receivingplaten 25 is normally in the on posi- 9 tion. When the sheet 22 dropsonto and slides down the platen 25 far enough to cover the cavity 35, avacuum is drawn behind the sheet, stopping it short of the mechanicalcatches 65 (FIGQ When a predetermined vacuum is reached a vacuum switchVSl closes and this causes the solenoid valve SVl to be shifted to theoff position allowing the sheet 22 to slide down against the catches 65(FIG. 8). After a delay of approximately 0.2 second solenoid valve 8V2(FlG. which controls the plate linear and rotary movement cylinders 44and 54 respectively, is energized in the .forward position, applying airto the head ends of the cylinders to beginmoving the platen from itsreceiving toward its deposit position. As soon as the platen 25 movesforward, a limit switch LS1 is tripped which, through appropriatecircuitry, restores vacuum solenoid valve 8V1 (FIG. 19) to the onposition, thereby restoring the vacuum in cavity so that the sheet 22 isagain held on the platen by vacuum during its continuing and subsequentforward and rotary movements.

When the platen 25 reaches the deposit position (FIG. 17) limit switchesLS2 and LS3 are contacted, with LS2 causing the vacuum solenoid 8V] toshift to the o position to release the vacuum in cavity 35, and LS3energizing a time delay circuit which, after 0.2 second, shifts thesolenoid valve S.V2 to the reverse position, applying air to the rodends of cylinders 44 and 54 to translate and pivot the platen 25,back toits receiving position (FIG. 18).

The handling section B, which includes the platen 25 and the associatedcylinders 44 and 54, is movable back and forth on the rollers 96 bymeans of cylinder 100 acting on frame 43. This cylinder is controlled bytwo solenoid valves 8V3 and 8V4, with SV3 being designed to supply airto the head end of the cylinder from either the plant air supply, forinitialextension of the frame into operating position; or from the tank102 which is maintained at 8 psi, for biasing the frame toward thereceiving means. in operation, SV3 acts to shift the source of the airflow to the head end of cylinder 100 between the plant air supply andthe tank 102; while SV4 controls the flow of air to and from the rod endof cylinder 100, either supplying air when 8V4 is in the reverseposition or exhausting to atmosphere when 8V4 is in the forwardposition.

To start a cycle the solenoid valves 8V3 and 8V4 are manually energizedto their respective forward positions (FIG. 20) by means of a mainloader switch M81 (FIG. 21). The frame 43 will then move forward underabout 17 psi pressure until the stop rods 103 contact the backingsurface. 104 of the buck 27. When the pressure builds up to 20 psi,pressure switch PS1 (FIG. 20) causes 8V3 to shift to tank 102 as thesource of air and leaves 8V4 in its forward, or exhaust position. Thetank 102 then maintains a constant 8 psi on the head end of the cylinderto provide the biasing force against the stack of sheets until MS]. isagain energized manually. As the frame 43 moves forward under theinfluence of cylinder 100 a limit switch LS4 is tripped starting thefeed conveyor 23 to transfer sheets to the conveyor section A. Asalready explained these sheets are transferred to the buck 27 by the,coordinated action of cylinders 44 and 54 and the vacuum on the platen25.

According to set up, when the buck his loaded to a stack thickness of 24(plus or minus 14) inches, limit ELECTRICAL CONTROL SYSTEM Referring toFIG. 21, the main switch'MSl includes a push button to initiate a cycleand a trip coil in circuit with the pressure switch PS1 to electricallydisengage the push button'when required.

In starting a cycle the push button acts to complete circuits throughlines 201, 202 and 203 to the forward coil of 8V4 and to the coil oflatch relay LR1. LRl is spring loaded in the open position and when itscoil is energized its contacts are closed to complete a circuit throughline 204 to the coil of SV3 to place it in its forward position.

When 20 psi is reached at cylinder 100, the pressure switch PS1 closes,energizing the coil on MS! which disengages the pushbutton and breaksthe circuits to the forward side of 5V4 and to LR1. SV4 will remain inthe forward position until the reverse coil is energized; however, SV3is spring loaded, so that when its forward coil is deenergized, bybreaking of the circuit through line 204, it is automatically shifted tothe tank 102 (see FIG. 20). t

When limit switch LS5 is closed by filling of the buck 27, time delayrelay TDRl is energized. TlDR1 allows sufficient time for the loader toclear and then completes a circuit through line 205, the deenergizedpush button switch and line 206 to the reverse coil of SV4 thusretracting the loader and allowing the buck 27 to be removed. TDR1allows enough time for full retraction and then times out leaving thereverse coil of SV4 open for the start of another cycle.

As shown in FIG. 21, the circuits controlling the cylinders 44 and 54and the vacuum pump are in position for the start of a cycle. Circuitbreaker 207 on latch relay LR2 is closed to complete a circuit throughlimit switch LS2, and lines 208 and 209 on the on coil of vacuumsolenoid 5V1. When a sheet covers the cavity 35 to complete the vacuumcircuit the vacuum builds up to a selected value at which point vacuumswitch V81 closes, completing a circuit through limit switch LS1 to coil210 of latch relay LR2. When coil 210 is energized circuit breaker 207opens the circuit to the on coil and closes a circuit via lines 211 and212 to a time delay relay TDR2, and circuit breaker 213 closes a circuitthrough lines 214 and 215 to the off coil of 8V1.

TDR2 delays 0.2 second and then completes a circuit through the forwardcoil of SV2 applying air to the head ends of cylinders 44 and 54 to movethe platen 25 from its receiving to its deposit position. when TDRZtimes out SV2 remains in the forward position. When LS1 is tripped bythe platen 25, a circuit, through line 216 is completed to coil 217 oflatch relay LR2 which opens circuit breaker 213 and closes circuitbreaker 207 through LS2 and across lines 208 and 209 to again energizethe on coil of SVl to restore the vacuum in cavity 35.

When LS2 is tripped by the platen in the deposit position, the circuitto the on coil of 8V! is open and a circuit through line 218 completedto energize the off" coil of SV] for deposit of the sheets. When LS3 istripped, a time delay relay TDR3 is energized, which allows a 0.2 seconddelay and then completes a circuit through line 219 to the reverse coilof 8V2 to cause the platen 25 to return to its receiving position. Asthe platen returns, LS1, LS2 and LS3 are returned to their originalpositions.

It is to be understood that the forms'of the invention herewith shownand described are to be taken as preferred embodiments only of the same,and that various changes in the shape, size and arrangement of parts aswell as various procedural changes may be resorted to without departingfrom the spirit of the invention.

We claim:

1. ln sheet handling apparatus the combination, with means forsupporting and conveying a succession of sheets horizontally along adefinite path, and sheet storing means remote therefrom; of meanspositioned therebetween for transferring sheets from the former to thelatter comprising a platen having a sheet supporting face thereon, meansfor locating said platen with said face at an angle to the horizontaland inclined upwardly toward said supporting and conveying means toreceive sheets dropping off an end of said conveying means, means forretaining a sheet so received on said face, means for horizontallymoving said inclined platen from said conveying means toward saidstoring means and then for swinging the same about a horizontal axis tobring said face from said inclined receiving angle to a discharge angleat the opposite side of the vertical from said receiving angledposition, and means for releasing a retained sheet from said face aftersaid platen arrives at said discharge angle and adjacent to said sheetstoring means.

2. Apparatus as defined in claim 1 in which said means for retaining asheet received on said supporting face includes means for selectivelypreventing relative movement between said sheet and said face whichcomprises vacuum means carried by said platen and communicating withsaid sheet supporting face for holding a sheet thereagainst; said vacuummeans comprising a cavity formed in said platen capable of being coveredby a sheet received on said supporting surface, and means for drawing avacuum in said cavity when it is covered by a sheet.

3. Apparatus as defined in claim 2, which includes means responsive tothe magnitude of the vacuum established within said cavity for releasingsaid vacuum when it reaches a predetermined level.

4. Apparatus as defined in claim 1, in which said means for retaining asheet received on said face includes a mechanical catch member carriedby said platen and selectively movable from an operative positionprotruding from said sheet supporting face and engageable with an edgeof a sheet supported thereon, to a retracted position behind said face.

5. Apparatus as defined in claim 2, in which said means for preventingrelative movement between said sheet and said supporting face alsoincludes a plurality of catch members carried by said platen andselectively movable from an operable position protruding from said sheetsupporting face below said cavity and engageable with the leading edgeof -a sheet when said platen is in its receiving position to a retractedposition behind said face when said platen is in its depositingposition, and means for selectively releasing said vacuum to permit asheet to slide down said face and onto said catch members.

6. Apparatus as defined in claim 5, including control means operable torestore the vacuum in said cavity when said sheet contacts said catchmeans, to initiate movement of said platen from said conveying meanstoward said storing means and swinging of the same from said receivingto said depositing positions, and to release said vacuum when saidsupporting face is at said storing means whereby to deposit said sheetthereon.

7. Apparatus as defined in claim 6, in which said control meanscomprises time delay means actuated upon attainment of a predeterminedvacuum in said cavity.

8. Apparatus for handling sheets as claimed in claim 5, in which each ofsaid catch member comprises a substantially L-shaped member having oneleg pivotally mounted on said platen and the other leg engageable with asheet on said supporting face, resilient means maintaining said otherleg in a sheet-engaging position protruding from said sheet-supportingface, an actuating rod having one end connected to said L-shaped memberat a point spaced from its pivot point and the other end journaled in alinear bearing mounted in a fixed position relative to said platen, andstop means formed on said rod and engageable with said bearing when saidplaten moves from its receiving to its depositing position, said stopmeans engaging said bearing before said platen reaches said depositposition, the continued movement of said platen causing said catch topivot about its mounting against the force of said resilient means.

9. In apparatus for receiving each of a succession of horizontallydisposed sheets and stacking said sheets on edge in face-to-facerelationship, a transfer mechanism including a horizontally disposedconveyor on which said sheets are deposited, said conveyor comprising afirst, stationary frame supporting the input end of said conveyor, asecond frame supporting the discharge end of said conveyor andhorizontally movable relative to the first in the direction of travel ofsaid conveyor; a support member spaced from said discharge end andhaving a horizontal supporting surface and a vertical backing surfaceformed thereon to receive sheets on edge; biasing means applying a forceagainst said movable frarne urging said frame toward said supportmember; a platen mounted on said movable frame beyond said discharge endfor translatory movement toward and away from said discharge end and forswinging movement about an axis translatable with said platen anddisposed below the plane of said conveyor; a sheet supporting surfaceformed on said platen; means for translating said platen from areceiving position adjacent said discharge end to a depositing positionadjacent said support member; means for swinging said platen back andforth about said axis from a receiving angle wherein said supportingsurface is inclined upwardly toward said conveyor to receive a sheet asit drops from said discharge end to a depositing angle wherein saidsupporting surface is substantially vertically disposed face-to-facewith said backing surface,

stop means carried by said movable frame and engageable with saidvertical backing surface to limit movement of said frame by said biasingmeans; and means for selectively preventing relative movement betweensaid sheet and said supporting surface when a sheet is received thereonand as said platen is translated and then swung from its receiving toits depositing angle, and for releasing said sheet after said platenreaches said deposting angle to deposit said sheet on said supportmember.

Po-wo WUNITED STATES PATENT [OFFICE CERTIFICATE OF CORRECTION Patent 3,774, 783 Dated November 27, 1973 Alfred H. Miller and George A. DeanInventor(s) It is certified thaf' error appears in the above-identifiedpatent 'and that said Letters Patent are hereby corrected as shownbelow:

Col.

, line 7, "plate" should be --p1aten-- line 66, "1/2" should be --27--line 67, "24**" should be --24 1/2-- Signed and sealed this 16th day ofApril 19m.

(SEAL) Atte st:

EDWARD M.FLETCHER,J'R. C MARSHALL DANN. Attesting Officer Commissionerof Patents

1. In sheet handling apparatus the combination, with means forsupporting and conveying a succession of sheets horizontally along adefinite path, and sheet storing means remote therefrom; of meanspositioned therebetween for transferring sheets from the former to thelatter comprising a platen having a sheet supporting face thereon, meansfor locating said platen with said face at an angle to the horizontaland inclined upwardly toward said supporting and conveying means toreceive sheets dropping off an end of said conveying means, means forretaining a sheet so received on said face, means for horizontallymoving said inclined platen from said conveying means toward saidstoring means and then for swinging the same about a horizontal axis tobring said face from said inclined receiving angle to a discharge angleat the opposite side of the vertical from said receiving angledposition, and means for releasing a retained sheet from said face aftersaid platen arrives at said discharge angle and adjacent to said sheetstoring means.
 2. Apparatus as defined in claim 1 in which said meansfor retaining a sheet received on said supporting face includes meansfor selectively preventing relative movement between said sheet and saidface which comprises vacuum means carried by said platen andcommunicating with said sheet supporting face for holding a sheetthereagainst; said vacuum means comprising a cavity formed in saidplaten capable of being covered by a sheet received on said supportingsurface, and means for drawing a vacuum in said cavity when it iscovered by a sheet.
 3. Apparatus as defined in claim 2, which includesmeans responsive to the magnitude of the vacuum established within saidcavity for releasing said vacuum when it reaches a predetermined level.4. Apparatus as defined in claim 1, in which said means for retaining asheet received on said face includes a mechanical catch member carriedby said platen and selectively movable from an operative positionprotruding from said sheet supporting face and engageable with an edgeof a sheet supported thereon, to a retracted position behind said face.5. Apparatus as defined in claim 2, in which said means for preventingrelative movement between said sheet and said supporting face alsoincludes a plurality of catch members carried by said platen andselectively movable from an operable position protruding from said sheetsupporting face below said cavity and engageable with the leading edgeof a sheet when said platen is in its receiving position to a retractedposition behind said face when said platen is in its depositingposition, and means for selectively releasing said vacuum to permit asheet to slide down said face and onto said catch members.
 6. Apparatusas defined in claim 5, including control means operable to restore thevacuum in said cavity when said sheet contacts said catch means, toinitiate movement of said platen from said conveying means toward saidstoring means and swinging of the same from said receiving to saiddepositing positions, and to release said vacuum when said supportingface is at said storing means whereby to deposit said sheet thereon. 7.Apparatus as defined in claim 6, in which said control means comprisestime delay means actuated upon attainment of a predetermined vacuum insaid cavity.
 8. Apparatus for handling sheets as claimed in claim 5, inwhich each of said catch member comprises a substantially L-shapedmember having one leg pivotally mounted on said platen and the other legengageable with a sheet on said supporting face, resilient meansmaintaining said other leg in a sheet-engaging position protruding fromsaid sheet-supporting face, an actuating rod having one enD connected tosaid L-shaped member at a point spaced from its pivot point and theother end journaled in a linear bearing mounted in a fixed positionrelative to said platen, and stop means formed on said rod andengageable with said bearing when said platen moves from its receivingto its depositing position, said stop means engaging said bearing beforesaid platen reaches said deposit position, the continued movement ofsaid platen causing said catch to pivot about its mounting against theforce of said resilient means.
 9. In apparatus for receiving each of asuccession of horizontally disposed sheets and stacking said sheets onedge in face-to-face relationship, a transfer mechanism including ahorizontally disposed conveyor on which said sheets are deposited, saidconveyor comprising a first, stationary frame supporting the input endof said conveyor, a second frame supporting the discharge end of saidconveyor and horizontally movable relative to the first in the directionof travel of said conveyor; a support member spaced from said dischargeend and having a horizontal supporting surface and a vertical backingsurface formed thereon to receive sheets on edge; biasing means applyinga force against said movable frame urging said frame toward said supportmember; a platen mounted on said movable frame beyond said discharge endfor translatory movement toward and away from said discharge end and forswinging movement about an axis translatable with said platen anddisposed below the plane of said conveyor; a sheet supporting surfaceformed on said platen; means for translating said platen from areceiving position adjacent said discharge end to a depositing positionadjacent said support member; means for swinging said platen back andforth about said axis from a receiving angle wherein said supportingsurface is inclined upwardly toward said conveyor to receive a sheet asit drops from said discharge end to a depositing angle wherein saidsupporting surface is substantially vertically disposed face-to-facewith said backing surface; stop means carried by said movable frame andengageable with said vertical backing surface to limit movement of saidframe by said biasing means; and means for selectively preventingrelative movement between said sheet and said supporting surface when asheet is received thereon and as said platen is translated and thenswung from its receiving to its depositing angle, and for releasing saidsheet after said platen reaches said deposting angle to deposit saidsheet on said support member.